welding spring steel

[Aussie Fitter Brendan]

hi i used the search and couldnt find any thing

so is it possilbe to properly and strongly weld spring steel


the reason i ask is because i am lookin into making and adjustable anti roll bar for a car
and if you go to the following page there is a picture of what i want to do

http://www.hrpworld.com/index.cfm?form_pic_id=1432_1&action=product_picture&form_cat_id=217,212,363

so is it posssilbe and if so what method(welding and cooling procedure is to be used

all info would be great

cheers Brendan

 

[Aussie Fitter Brendan]

would this be 4140 then heat treated

 

[pm]

you would probably be better of with a mechanical connection.

 

[johnoder]

Is the milled flat component rotateable? (I ask this as I see what looks like a bell crank or lever with linkage attached to it)

If so, it is the "spring" element , fits thru a socket that functions as a bearing and has no welding on it.

The "adjustment" in rate would vary as you rotated this element - more flat (presented normal to suspension travel) = less resistance in bending.

The "structure" (sockets, cross tube) would just be 4130 normalized tubing which has been welded on sucessfully for ages in the aircraft field.

John

 

[aametalmaster]

Good eyes John...Bob

 

[Aussie Fitter Brendan]

thanks for all the help

can i down load a specs sheet for all the grades of steel (4130,4140 etc)

so john wat do you think would be the way to construct the spring element

cheers brendan

 

[johnoder]

so john wat do you think would be the way to construct the spring element

4140 prehard (I.E., low thirties on Rockwell C scale) round bar, lathe and mill work to suit, no welding. Before the industry dreamed up this term (prehard), we just called this stuff 4140 commercial heat treat.

6150 a little harder than above would be a better spring, but I do not expect you will come across any

Some of the aircraft supply houses (such as Aircraft Spruce in California USA) used to sell 6150 round bar, but you would need to take care of the heat treat required, and this is not a do it yourself process.

Any such machined spring element will need very nice finishes and no tool marks / sharp corners if you want it to live awhile. Busted parts of this fancy anti roll bar are not likely something you want

John

 

[Aussie Fitter Brendan]

true
would shot penning help reduce stress fractures and breakage

brendan

 

[HelicalCut]

Shot peening the root radius of the spring (the rotatable tapered plate on each end would be the main area to watch for. this radius is important. Get the taper right as well I am guessing that it is profiled to give constant stress in bending thereby making best use of the material properties. Don't get overly fussy if the material is run within reasonable stress limits it will survive. similar to the springs on your car in other words good design will go a long way towards making this part live.

 

[Aussie Fitter Brendan]

thanks hc

also another quick question when welding 4130

tig?... filler wire type heat etc
or
arc??.. rod type etc

 

[johnoder]

Tig and this stuff does real well on 4130

Filler Metal

John